Available online http://ccforum.com/content/9/6/R808
Research
Open Access
Vol 9 No 6
Long term effect of a medical emergency team on cardiac arrests in a teaching hospital Daryl Jones1, Rinaldo Bellomo2, Samantha Bates3, Stephen Warrillow4, Donna Goldsmith5, Graeme Hart6, Helen Opdam7 and Geoffrey Gutteridge8 1Clinical
Fellow, Department of Intensive Care, Alfred Hospital, Commercial Road, Prahran, Melbourne, Victoria 3181, Australia of Research, Department of Intensive Care and Department of Surgery (Melbourne University), Austin Hospital, Studley Road, Heidelberg, Melbourne, Victoria 3084, Australia 3Research Nurse, Department of Intensive Care and Department of Surgery (Melbourne University), Austin Hospital, Studley Road, Heidelberg, Melbourne, Victoria 3084, Australia 4Staff Specialist, Department of Intensive Care and Department of Surgery (Melbourne University), Austin Hospital, Studley Road, Heidelberg, Melbourne, Victoria 3084, Australia 5Research Nurse, Department of Intensive Care and Department of Surgery (Melbourne University), Austin Hospital, Studley Road, Heidelberg, Melbourne, Victoria 3084, Australia 6Staff Specialist, Department of Intensive Care and Department of Surgery (Melbourne University), Austin Hospital, Studley Road, Heidelberg, Melbourne, Victoria 3084, Australia 7Staff Specialist, Department of Intensive Care and Department of Surgery (Melbourne University), Austin Hospital, Studley Road, Heidelberg, Melbourne, Victoria 3084, Australia 8Staff Specialist, Department of Intensive Care and Department of Surgery (Melbourne University), Austin Hospital, Studley Road, Heidelberg, Melbourne, Victoria 3084, Australia 2Director
Corresponding author: Rinaldo Bellomo,
[email protected] Received: 15 Aug 2005 Accepted: 19 Oct 2005 Published: 16 Nov 2005 Critical Care 2005, 9:R808-R815 (DOI 10.1186/cc3906) This article is online at: http://ccforum.com/content/9/6/R808 © 2005 Jones et al.; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract Introduction It is unknown whether the reported short-term reduction in cardiac arrests associated with the introduction of the medical emergency team (MET) system can be sustained. Method We conducted a prospective, controlled before-andafter examination of the effect of a MET system on the long-term incidence of cardiac arrests. We included consecutive patients admitted during three study periods: before the introduction of the MET; during the education phase preceding the implementation of the MET; and a period of four years from the implementation of the MET system. Cardiac arrests were identified from a log book of cardiac arrest calls and crossreferenced with case report forms and the intensive care unit admissions database. We measured the number of hospital admissions and MET reviews during each period, performed multivariate logistic regression analysis to identify predictors of mortality following cardiac arrest and studied the correlation between the rate of MET calls with the rate of cardiac arrests. Results Before the introduction of the MET system there were 66 cardiac arrests and 16,246 admissions (4.06 cardiac arrests
per 1,000 admissions). During the education period, the incidence of cardiac arrests decreased to 2.45 per 1,000 admissions (odds ratio (OR) for cardiac arrest 0.60; 95% confidence interval (CI) 0.43–0.86; p = 0.004). After the implementation of the MET system, the incidence of cardiac arrests further decreased to 1.90 per 1,000 admissions (OR for cardiac arrest 0.47; 95% CI 0.35–0.62; p < 0.0001). There was an inverse correlation between the number of MET calls in each calendar year and the number of cardiac arrests for the same year (r2 = 0.84; p = 0.01), with 17 MET calls being associated with one less cardiac arrest. Male gender (OR 2.88; 95% CI 1.34–6.19) and an initial rhythm of either asystole (OR 7.58; 95% CI 3.15–18.25; p < 0.0001) or pulseless electrical activity (OR 4.09; 95% CI 1.59–10.51; p = 0.003) predicted an increased risk of death. Conclusion Introduction of a MET system into a teaching hospital was associated with a sustained and progressive reduction in cardiac arrests over a four year period. Our findings show sustainability and suggest that, for every 17 MET calls, one cardiac arrest might be prevented.
CI = confidence interval; ICU = intensive care unit; MET = medical emergency team; OR = odds ratio.
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Critical Care
Vol 9 No 6
Jones et al.
Introduction Despite advances in medical technology and the introduction of cardiac arrest teams, the mortality of in-hospital cardiac arrests remains high (approximately 85% [1]). Up to 80% of patients suffering cardiac arrests have signs of physiological instability (alterations in the commonly measured vital signs) in the 24 hour period before the event [2-4]. In response to this observation, hospitals are increasingly implementing specialized teams (variably named medical emergency teams (METs), rapid response teams, or outreach teams) to identify, review and treat unstable ward patients in the early phase of deterioration, with the goal of preventing cardiac arrests [5-8]. METs have been shown to reduce the incidence of cardiac arrests in hospitalized patients in short-term before-and-after studies [5-7]. DeVita and co-workers [8] have recently reported a 17% reduction in cardiac arrests in the 1.8 years after increased use of the MET service in a teaching hospital [8]. The effectiveness of METs in achieving or sustaining this outcome for periods greater than this has not been shown to date. Since the introduction of the MET service in our hospital, we have conducted an educational campaign to improve awareness in an attempt to increase use of the service. Sustained system change, however, requires a strong organizational commitment to safety [9] as well as continued education and awareness-raising activities. Institutionalization of system change may fail because of turnover of key employees [10] such as doctors and nurses. This may result in the introduction of new staff who are unfamiliar with the MET concept [8,11]. Thus, there is uncertainty that the MET system will continue to deliver any benefits that might have been demonstrated immediately after its introduction. In this study, we analyzed the incidence of cardiac arrests in the four years following the introduction of the MET service.
Materials and methods The hospital The Austin Hospital is a 400 bed acute care hospital affiliated with the University of Melbourne. The hospital provides services such as cardiothoracic surgery and neurosurgery and is also the referral center for acute spinal injuries and liver transplantation for the state of Victoria. The intensive care unit (ICU) has 21 beds and receives approximately 2,000 admissions per year. Ethics approval Approval was obtained from the Institution's Ethics Committee for implementation of the MET system and collection of the data related to it. The need for informed consent was waived by the committee.
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Medical emergency responses The acute care hospital has two levels of emergency response. The traditional 'Code Blue' call is intended for resuscitation of cardiac arrests and other sudden life-threatening medical emergencies. It consists of an anesthetic fellow, a coronary care fellow and nurse, an ICU fellow and nurse, as well as the Medical fellow of the receiving unit of the day. The MET is intended to review all medical emergencies other than cardiac arrests, and has been described in detail previously [7,12]. It consists of an ICU fellow and nurse, as well as the Medical fellow of the receiving unit of the day. It can be activated by any member of hospital staff according to pre-determined criteria that are based primarily on abnormalities of vital signs and clinical status. Specifically, the criteria include acute changes in heart rate (130 beats/minute), systolic blood pressure (